Field of the Invention
The present invention relates to an intermediate transfer member, a method of manufacturing an intermediate transfer member, and to an image forming method.
Description of the Related Art
In recent years, an image forming method and an image forming apparatus using an ink jet system have been attracting attention as technologies suited to meet market demands for a shift to wide-variety small-lot production of printed matter and reduction in delivery time. However, the image formation using the ink jet system may cause a phenomenon that adjacent dots of applied ink are mixed with each other (bleeding) or a phenomenon that ink landed first is attracted by ink landed later (beading). Further, the image formation using the ink jet system may cause a curling phenomenon or a cockling phenomenon due to excessive absorption of a liquid component of ink by a recording medium.
To prevent those phenomena, there is proposed an image recording method that involves transferring, onto a recording medium, an intermediate image formed by applying ink onto an intermediate transfer member, to thereby obtain an image (transfer-type ink jet recording method). In Japanese Patent Application Laid-Open No. S59-225958, there is proposed an ink jet printer configured to form an image on a drum with dye ink and transfer the image onto a recording medium.
For the purpose of keeping the formed image satisfactorily by preventing the flow of ink applied onto the surface of the intermediate transfer member, there are many proposals that a treatment solution for reducing the fluidity of the ink be applied onto the intermediate transfer member before the ink image is formed.
It is preferred that the surface of the intermediate transfer member for use in the transfer-type ink jet recording method be formed of an elastic body so as to secure the uniformity of a pressure to be applied when an image is transferred onto a recording medium. It is also preferred that the intermediate transfer member have low surface free energy from the viewpoint of image transfer efficiency.
However, the intermediate transfer member having low surface free energy is liable to cause a phenomenon that the treatment solution is repelled or inwardly attracted due to surface tension of the treatment solution, thereby degrading the quality of the ink image formed afterwards. In general, such a phenomenon is liable to occur as the intermediate transfer member becomes smoother with lower surface roughness.
In Japanese Patent Application Laid-Open No. H07-017030, there is proposed that a fine uneven shape be formed on the surface of the intermediate transfer member formed of an elastic body made of silicone rubber or other materials, to thereby prevent the above-mentioned image degradation phenomenon that may be caused by the repellence or inward attraction of the treatment solution. As a method of manufacturing the intermediate transfer member having an uneven shape formed on its surface, in Japanese Patent Application Laid-Open No. H07-017030, there is proposed a forming method using a mold having a desired fine uneven shape.
In particular, there is given an embossing method using a mold generally referred to as “embossing roll”, which has an inverted shape of a desired uneven shape on the cylindrical peripheral surface. In this method, the embossing roll is brought into press contact with the surface of the elastic body to impart the uneven shape successively. Thus, this method is suited in terms of dimensional accuracy of the uneven shape and productivity.
It is preferred that the elastic body to be used for the surface of the intermediate transfer member be low in elastic modulus and easily deformable by pressure so as to secure the uniformity of the pressure with ease when an image is transferred onto a recording medium. In particular, the image transfer rate for a recording medium is liable to decrease when the image is transferred onto a recording medium having a rough surface or the transfer time is short. Therefore, the elastic body is required to have a particularly low elastic modulus.